One of the most persistent and troublesome problems arising during modern fabric laundering operations is the tendency of some colored fabrics to release dye into the laundering solutions. The dye is then transferred onto other fabrics being washed therewith.
One way of overcoming this problem would be to bleach the fugitive dyes washed out of dyed fabrics before they have the opportunity to become attached to other articles in the wash.
Suspended or solubilized dyes can to some degree be oxidized in solution by employing known bleaching agents.
GB 2 101 167 describes a stable liquid bleaching composition containing a hydrogen peroxide precursor which is activated to yield hydrogen peroxide on dilution.
However it is important at the same time not to bleach the dyes actually remaining on the fabrics, that is, not to cause color damage.
U.S. Pat. No. 4,077,768 describes a process for inhibiting dye transfer by the use of an oxidizing bleaching agent together with a catalytic compound such as iron porphins.
Copending EP Patent Application 91202655.6 filed Oct. 9, 1991, relates to dye transfer inhibiting compositions comprising an enzymatic system capable of generating hydrogen peroxide and porphin catalysts.
Due to the presence of the oxidizing agents, the detergent enzymes such as protease, lipase, amylase, cellulase formulated with said dye transfer inhibiting composition have to perform their enzymatic activity in an oxidative environment, with a consequent loss of activity, especially in the absence of any bleeding dye.
It has now been found that improved stability of enzymes formulated with said enzymatic dye transfer inhibiting composition can be achieved by additing enzyme oxidation scavengers.
According to one embodiment of this invention an anzymatic dye transfer inhibiting composition is provided which is fully compatible with other enzymes and yet exhibits optimum dye transfer inhibiting benefits.
Accordingly, a dye transfer inhibiting composition is provided which exhibits optimum dye transfer inhibiting properties.
According to another embodiment, the invention provides an efficient process for laundering operations involving colored fabrics.